It turns out that in addition to accusations they have been breeding animals for circuses (kind of frowned upon these days), The New Humanist reports that:

…it was discovered that the body of a tiger which died during childbirth at the zoo was disposed of in a way that contravenes animal disposal regulations – its paws, head and skin were removed, the carcass was buried on owner Anthony Bush’s land, and the head was revealed to have been kept in a freezer at the zoo.